Ink-jet recorder, semiconductor device, and recording head device

ABSTRACT

A carriage (recording head portion) which an ink cartridge including a non-volatile memory is to be mounted has a memory access controlling portion for controlling accesses to a non-volatile memory, thereby reducing the number of connection lines between the carriage (recording head portion) and a printer main body controlling portion. The apparatus main body controlling portion and the memory access controlling portion transmit and receive data therebetween by serial data communication. The memory access controlling portion reads out various information (the amount of remaining ink, use start year and month, and the like) stored in each non-volatile memory and then stores the readout information in a RAM in the memory access controlling portion. The apparatus main body controlling portion issues an access request command for the RAM to read information out from the RAM and update the readout information. When a printer is powered off, the apparatus main body controlling portion issues a write back command. The memory access controlling portion writes the information in the RAM back to the non-volatile memory.

TECHNICAL FIELD

The present invention relates to a recording apparatus having a non-volatile memory in a recording material accommodating cartridge so that various data (remaining amount data, use start date data, recording material type data, manufacturing managing data, etc.) on a cartridge can be stored in the non-volatile memory to manage the usage of each cartridge, and in particular, to a recording apparatus having an interface circuit (memory access controlling circuit) between a control portion of a recording apparatus main body and the non-volatile memory to reduce the amount of processing to be executed by the control portion to access the non-volatile memory, as well as a semiconductor device for use as the interface and a recording head apparatus comprising the interface circuit (memory access controlling circuit).

BACKGROUND ART

Japanese Patent Laid-Open No. 62-184856 (Japanese Patent No. 2594912) describes an ink cartridge and a recording apparatus in which the ink cartridge has a non-volatile memory in which data corresponding to the amount of remaining ink are stored in order to manage the amount of remaining ink for each cartridge.

Japanese Patent Laid-Open No. 8-197748 describes an ink jet printer including an ink cartridge having a non-volatile memory in which ID information is stored and a printer main body correlating the ID information for the ink cartridge read out from the non-volatile memory with the amount of remaining ink so as to eliminate the need to redetect the amount of remaining ink when an ink cartridge with the same ID information is reinstalled.

The above-described conventional recording apparatus and other devices are structured such that when an ink cartridge is installed at a predetermined position, a plurality of electrodes provided in the ink cartridge are electrically connected to a plurality of electrodes provided in an ink cartridge installing portion to allow a power supply to the non-volatile memory provided in the ink cartridge and transmission and reception of various signals to and from the non-volatile memory.

The conventional apparatus, however, is structured such that a power supply and various signal terminals of the non-volatile memory are all electrically drawn out and connected to a control portion of a printer apparatus main body, so that a large number of connection lines are present between the ink cartridge installed portion and the control portion of the printer apparatus main body. This may make it difficult to wire the connection lines. In particular, in a structure in which the ink cartridge is installed in a carriage including a recording head, a flexible cable must be used to electrically connect the carriage and the printer apparatus main body together so as to enable the movement of the carriage. As a result, an increase in the number of cores in the flexible cable may undesirably increase the amount of force required to move the carriage. Furthermore, if a plurality of ink cartridges are installed in the carriage, the number of connection lines increases in proportion to the number of ink cartridges. For example, in a structure using two types of ink cartridges including a black and a color ones, terminals of the non-volatile memory which are provided for the corresponding cartridges must each be drawn out, thereby doubling the number of required signal lines.

The present invention is provided to solve these problems, and it is an object thereof to provide an ink jet recording apparatus wherein a carriage in which an ink cartridge is installed has an interface circuit (memory access controlling circuit) comprising a function of accessing a non-volatile memory and a function of communicating data to and from a printer apparatus main body, thereby making it possible to reduce the number of connection lines between an ink cartridge installed portion and the printer apparatus main body, as well as a semiconductor device and a recording head device both serving to achieve this purpose.

DISCLOSURE OF THE INVENTION

An ink jet recording apparatus according to the present invention is characterized by having a memory access controlling portion in a carriage including a housing portion for an ink cartridge including a non-volatile memory, the memory access controlling portion controlling data transmissions and receptions between a control portion of a recording apparatus main body and the non-volatile memory based on commands from the control portion of the recording apparatus main body.

The carriage has the memory access controlling portion, via which the non-volatile memory is accessed, thereby making it possible to reduce the number of connection lines between the carriage and the control portion of the recording apparatus main body.

The memory access controlling portion preferably comprises a serial data communicating means for executing serial data communication with the control portion of the recording apparatus main body, a command executing portion for executing a command supplied by the control portion of the recording apparatus main body, and a non-volatile memory write and readout controlling portion for executing writes to and readouts from the non-volatile memory.

The use of the serial data communication reduces the number of connection lines between the carriage and the control portion of the recording apparatus main body.

Further, the memory access controlling portion preferably comprises a serial data communicating means for executing serial data communication with the control portion of the recording apparatus main body, a command executing portion for executing a command supplied by the control portion of the recording apparatus main body, a non-volatile memory write and readout controlling portion for executing writes to and readouts from the non-volatile memory, and a temporary storage means for temporarily storing data read out from the non-volatile memory.

The memory access controlling portion has the temporary storage means such as a random access memory in which data read out from the non-volatile memory are all stored so that the stored data can be read out in response to a data readout request from the apparatus main body controlling portion, thus making it possible to respond to data readout requests at a high speed. Furthermore, after generating a data read out request to renew the data in the temporary storage means, the apparatus main body controlling portion can generate a data write request for the non-volatile memory to cause the renewed data to be written to the non-volatile memory. Accordingly, even with a plurality of data items to be renewed, the plurality of data can be written to the non-volatile memory with a single write operation.

Additionally, the memory access controlling portion desirably comprise a power supply controlling portion for controlling a power supply to the non-volatile memory.

The power supply controlling means enables power supply to the non-volatile memory only when it is accessed. This makes it possible to reduce unwanted power consumption. Further, the power supply is stopped while the non-volatile memory is not accessed, thereby preventing the data stored in the non-volatile memory from being rewritten due to noise or the like.

The non-volatile memory write and readout controlling means is desirably configured to be able to output plural types of clocks for executing at least either a write to or a readout from the non-volatile memory and to select from these clocks depending on the electrical characteristics of the non-volatile memory. When the plural types of clocks of different pulse widths are provided and selected from depending on the electrical characteristics of the non-volatile memory, the points of time to execute a readout from or a write to the non-volatile memory can be appropriately set.

Further, the memory access controlling portion is desirably configured to be able to access a plurality of non-volatile memories.

This configuration prevents the number of connection lines between the carriage and the control portion of the recording apparatus from being increased despite an increase in the number of non-volatile memories.

The use of a semiconductor device (integrated circuit device) for the memory access controlling portion facilitates the provision of the memory access controlling portion in the carriage including the housing portion of the ink carriage and serves to reduce the size of the carriage.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the entire configuration of an ink jet recording apparatus according to the present invention;

FIG. 2 is a block diagram showing a specific example of a non-volatile memory;

FIG. 3 is a view useful in explaining information stored in the non-volatile memory;

FIG. 4 is a view useful in explaining an example of information stored in a non-volatile memory provided in a black ink cartridge;

FIG. 5 is a view useful in explaining an example of information stored in a non-volatile memory provided in a color ink cartridge;

FIG. 6 is a block diagram showing a specific example of a memory access controlling portion;

FIG. 7 is a view useful in explaining the names of terminals (signal names) of an integrated circuit for a memory access controlling portion and their functions;

FIG. 8(A) is a view showing a command of an 8-bit fixed length supplied by an apparatus main body controlling portion when a command mode designating signal is at an L level;

FIG. 8(B) is a view showing a command of a variable length supplied by an apparatus main body controlling portion when the command mode designating signal SEL is at an H level;

FIG. 9 is a block diagram of a reception controlling portion;

FIG. 10 is a view useful in explaining timings for switching a command mode designating signal;

FIG. 11 is a view useful in explaining specifications on a variable-length command and of a response thereto;

FIG. 12 is a view useful in explaining the contents of a group of control registers and their functions;

FIG. 13 is a view useful in explaining information stored in a RAM;

FIG. 14 is a block diagram of a transmission controlling portion;

FIG. 15(A) is a view useful in explaining the format of serially communicated data less than 8 bits;

FIG. 15(B) is a view useful in explaining the format of serially communicated data more than 8 bits;

FIG. 16 is a perspective view showing the structure of a printing mechanism portion of an ink jet printer with a recording apparatus according to the present invention applied thereto;

FIG. 17 is a perspective view showing that a carriage is disassembled into a holder portion and a header portion;

FIG. 18(A) is a perspective view of a black ink cartridge;

FIG. 18(B) is a perspective view of a color ink cartridge;

FIG. 18 is a perspective view of an ink cartridge;

FIG. 19(A) is a perspective view showing the structure of a front surface side of a non-volatile memory circuit substrate;

FIG. 19(B) is a perspective view showing the structure of a rear surface side of a non-volatile memory circuit substrate;

FIG. 19(C) is a view useful in explaining the size of electrodes of the non-volatile memory circuit substrate;

FIG. 19(D) is a top view showing how the electrodes of the non-volatile memory circuit substrate contacts with contacts;

FIG. 19(E) is a side view showing how the electrodes of the non-volatile memory circuit substrate contacts with the contacts;

FIG. 20 is a view useful in explaining how an ink cartridge is installed;

FIG. 21 is a view useful in explaining how the ink cartridge is installed; and

FIG. 22(A) is a view showing how the non-volatile memory substrate is in contact with a contact constituting member of a contact mechanism before an ink supplying port in the ink cartridge comes into contact with an ink supplying needle of a holder;

FIG. 22(B) is a view showing how the non-volatile memory substrate is in contact with a contact constituting member of a contact mechanism when an ink supplying port in the ink cartridge comes into contact with an ink supplying needle of a holder;

FIG. 22(C) is a view showing how the non-volatile memory substrate is in contact with a contact constituting member of a contact mechanism when the ink supplying needle has fully entered the ink supplying port.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, an embodiment of the present invention will be described with reference to the drawings. In each of the figures referenced in the following description, parts equivalent to those in the other figures are denoted by the same reference numbers.

FIG. 1 is a block diagram showing the entire configuration of an ink jet recording apparatus according to the present invention. An ink jet recording apparatus 1 is composed of an apparatus main body controlling portion 2 provided in a recording apparatus main body, a memory access controlling portion 3 provided in a carriage comprising an ink cartridge installing portion, a non-volatile memory 4 provided in a black ink cartridge, a non-volatile memory 5 provided in a color ink cartridge, and a recording controlling mechanism (not shown; a mechanism for controlling sheet feeding, carriage movement, ink ejection, and the like). The non-volatile memories 4 and 5 are, for example, EEPROMs that allow electric writes there to and electric read outs there from. Although FIG. 1 shows a configuration comprising the two non-volatile memories 4 and 5, any number of non-volatile memories may be used.

The apparatus main body controlling portion 2 controls the entire operation of the ink jet recording apparatus 1 and comprises a microcomputer system. Various commands and data are transmitted and received between the apparatus main body controlling portion 2 and the memory access controlling portion 3 by means of serial data communication. The non-volatile memories 4 and 5 are of what is called a bit sequential access type that allows data to be written thereto and read out therefrom in a bit serial manner.

The memory access controlling portion 3 comprises a serial data communicating means 3 a for executing serial data communication with the apparatus main body controlling portion 2, a command executing means 3 b for executing a command supplied by the apparatus main body controlling portion 2, a non-volatile memory write and readout controlling means 3 c for executing writes to and readouts from the non-volatile memories 4, 5, a temporary storage means (RAM) 3 d for temporarily storing data readout from the non-volatile memory, and a power supply controlling means 3 e for controlling a power supply to the non-volatile memory.

The apparatus main body controlling portion 2 issues a command for reading out data from the non-volatile memories 4 and 5 to cause the non-volatile memory write and readout controlling means 3 c to read out various data from the non-volatile memory 4 or 5. The various data read out from the non-volatile memories 4 or 5 are stored in the temporary storage means (RAM) 3 d. The apparatus main body controlling portion 2 issues a readout command for the temporary storage means (RAM) 3 d to read out various data therefrom. The apparatus main body controlling portion 2 issues a write command for the temporary storage means (RAM) 3 d to write various data thereto. The apparatus main body controlling portion 2 issues a write command for the non-volatile memories 4 or 5 to the memory access controlling portion 3 so that data stored in the temporary storage means (RAM) 3 d can be stored in the non-volatile memories 4 or 5.

Thus, the ink jet recording apparatus 1 according to the present invention has the memory access controlling portion 3 between the apparatus main body controlling portion 2 and the non-volatile memories 4 and 5 so that the memory accesses controlling portion 3 can execute writes to and readouts from the non-volatile memories 4 and 5. Accordingly, the apparatus main body controlling portion 2 is not required to directly access the non-volatile memories 4 and 5, and a signal line for communicating data between the apparatus main body controlling portion 2 and the memory access controlling portion 3 has only to be provided. Consequently, the number of connection lines between the apparatus main body controlling portion 2 and the memory access controlling portion 3 can be substantially reduced.

Furthermore, since the apparatus main body controlling portion 2 is not required to directly access the non-volatile memories 4 and 5, the amount of processing to be executed by the apparatus main body controlling portion 2 can be reduced. Moreover, the memory access controlling portion 3 reads out data stored in the non-volatile memories 4 and 5 and stores them in the RAM 3 d. In response to a readout request issued by the apparatus main body controlling portion 2, data stored in the RAM are read out for a response, thereby enabling a fast response to the readout request.

Additionally, since the power supply controlling means 3 e is provided in the memory access controlling portion 3, power can be supplied to the non-volatile memories 4 and 5 only when the latter are accessed. This eliminates unwanted power consumption and prevents the data stored in the non-volatile memories 4 and 5 from being rewritten due to noise or the like while the non-volatile memories 4 and 5 are not being accessed.

The configuration of the ink jet recording apparatus 1 according to the present invention will be described below in detail with reference to FIGS. 2 to 22.

FIG. 2 is a block diagram showing a specific example of a non-volatile memory. The non-volatile memories 4 and 5 each comprise a memory cell 41, a read-write controlling portion 42 and an address counter 43. If a chip select signal CS is at an L level, the address counter 43 is reset to a count value of zero. If the chip select signal CS is at an H level, the address counter 43 performs an up-count operation based on a clock signal CK. Accordingly, when the chip select signal CS is changed to the H level, the address 0 is set, and whenever the clock signal CK is supplied, the address can be incremented.

In this case, two types of pulse widths (L-level pulse widths) of the clock signal CK are provided so that one of the clock signals of these two pulse widths can be selected. This selection is made using an input terminal ES for selecting a write time, described later. For example, a clock signal of 3.0-ms pulse width and a clock signal of 3.5-ms pulse width are provided. Then, one of the clock signals is appropriately selected depending on specifications on (electrical characteristics of) the EEPROM used as the non-volatile memories 4 and 5, and is then supplied to the non-volatile memories 4 and 5. When, however, the non-volatile memories 4 and 5 are operating, one of the clock signals is fixedly used and is not switched. Reads may be achieved using only one type of clock signal, but as in writes, an input terminal for selecting a read time as well as for example, two types of clock signals may be provided so that the terminal can be used to select one of the clock signals. As described above, selecting the clock signal makes it possible to appropriately set the readout and write times for the non-volatile memories 4 and 5.

If a read/write signal WR is at the L level, the read/write controlling portion 42 reads out data (1 bit) stored in a memory cell 41 at an address designated by the address counter 43 and outputs the readout data to a data input/output terminal IO. If the read/write signal WR is at the H level, the read/write controlling portion 42 writes data (1 bit) supplied to the data INPUT/OUTPUT terminal IO to the memory cell 41 at the address designated by the address counter 43.

FIG. 3 is a view useful in explaining information stored in the non-volatile memory. The non-volatile memories 4 and 5 has a storage capacity of 256 bits. The non-volatile memories 4 and 5 each store 35 information items.

Each information item has a variable bit length. The non-volatile memories 4 and 5 each store data of a variable length in a bit serial manner. This makes it possible to store a large amount of information in a limited storage capacity.

Data on the amount of remaining ink, data on the use start years and months of ink cartridges, that is, data that must be renewed depending on the user's usage of the ink cartridges are stored within the range of numbers 1 to 9 (information numbers 0 to 8 and 35 to 43) shown in FIG. 3. Thus, when the ink cartridges are actually used, data must be written (renewed) only to the lower addresses in the non-volatile memories 4 and 5. Accordingly, when the use of the ink jet recording apparatus 1 is ended and a power supply thereto is turned off, data within the range of numbers 1 to 9 (information numbers 0 to 8 and 35 to 43) shown in FIG. 3 have only to be written to the non-volatile memories 4 and 5.

The non-volatile memory 4 provided in the black ink cartridge stores data on the amount of remaining black ink, the use start year and month, and the like. The non-volatile memory 5 provided in the color ink cartridge stores data on the amount of remaining ink, the use start year and month, and the like for each color ink.

Various data that are not required to be renewed by the user are stored within the range of numbers 10 to 35 (information numbers 9 to 34 and 44 to 69) shown in FIG. 3.

Specifically, these data include data on the versions of the ink cartridges, ink types, the date of manufacture (year, month, and day) of the ink cartridges, the serial numbers thereof, manufacturing sites, recycling of the cartridges, etc.

FIG. 4 is a view useful in explaining an example of information stored in the non-volatile memory provided in the black ink cartridge. In FIG. 4, reference numeral 410 denotes a first storage area in which data for rewrite are stored, and reference numeral 420 denotes a second storage area in which readout only data are stored. The first storage area 410 are arranged at addresses that are accessed earlier than the second storage area 420 when the non-volatile memory 4 is accessed.

The data for rewrite stored in the first storage area 410 are first and second black ink remaining-amount data assigned to storage areas 411 and 412, respectively, according to an access order. The black ink remaining amount data are assigned to the two storage areas 411 and 412 because the data in these areas are alternately rewritten. Thus, if the data stored in the storage area 411 are the last rewritten data, the black ink remaining-amount data stored in the storage area 412 precede the last rewritten data and the data in the storage area 412 are to be written next.

The readout only data stored in the second storage area 420 are those on the opening times (year and month) of the ink cartridges, the versions of the ink cartridges, ink types such as pigments and dyes, the date of manufacture (year, month, and day) thereof, the production lines therefor, the serial numbers thereof, and the presence of recycling indicating whether the ink cartridge is new or recycled, which data are assigned to storage areas 412 to 430 according to an access order.

FIG. 5 is a view useful in explaining an example of information stored in the non-volatile memory provided in the color ink cartridge. In FIG. 5, reference numeral 510 denotes a first storage area in which data for rewrite are stored, and reference numeral 550 denotes a second storage area in which readout only data are stored. The first storage area 510 are arranged at addresses that are accessed earlier than the second storage area 550 when the non-volatile memory 5 is accessed.

The data for rewrite stored in the first storage area 510 are first and second cyan ink remaining-amount data, first and second magenta ink remaining-amount data, first and second yellow ink remaining-amount data, first and second light cyan ink remaining-amount data, and first and second light magenta ink remaining-amount data which are assigned to storage areas 511 to 520, respectively, according to an access order. The ink remaining amount data for each color are assigned to the two storage areas because the data in these areas are alternately rewritten as in the black ink cartridge.

The readout only data stored in the second storage area 550 are those on the opening times (year and month) of the ink cartridges, the versions of the ink cartridges, ink types such as pigments and dyes, the date of manufacture (year, month, and day) thereof, the production lines therefor, the serial numbers thereof, and the presence of recycling indicating whether the ink cartridge is new or recycled, which data are assigned to storage areas 551 to 560 according to an access order. Since these data are the same regardless of the colors, only the data for one color are stored as data common to all the colors.

FIG. 6 is a block diagram showing a specific example of the memory access controlling portion. The memory access controlling portion 3 is composed of a serial-data communicating portion 11, a reception controlling portion 12, a transmission controlling portion 13, an execution controlling portion 14, a mode register 15, a group of control registers 16, a first RAM 17, a second RAM 18, a non-volatile memory write and read controlling portion 19, an output controlling portion 20, an effective-bit-length data table 21, a clock generating portion 22, an oscillation circuit portion 23, a reset circuit portion 24, a testing control portion 25, and an information and address correlating table 26.

The serial data communicating portion 11, the reception controlling portion 12 and the transmission controlling portion 13 constitute the serial data communicating means 3 a shown in FIG. 1. The execution executing portion 14, the mode register 15, the group of registers 16, and the effective-bit-length data table 21 constitute the command executing means 3 b shown in FIG. 1. The non-volatile memory write and readout controlling portion 19, the effective-bit-length data table 21, and the information and address correlating table 26 constitute the non-volatile memory write and readout controlling portion 3 c shown in FIG. 1. The first RAM 17 and the second RAM 18 constitute the temporary storage means (RAM) 3 d shown in FIG. 1. The output controlling means 20 constitutes the power supply controlling means 3 e shown in FIG. 1.

The clock generating portion 22 divides the frequency of an oscillation output from the oscillating circuit portion 23 to obtain a clock TCLK as an output. As described previously, clocks TCLK of two types of pulse widths can be generated by selecting a frequency dividing ratio based on the signal provided to the input terminal ES of the clock generating portion 22. As a result, the points of time to execute readouts from and writes to the memories 4 and 5 can be appropriately set depending on the performance of the device.

In this embodiment, the memory access controlling portion 3 is implemented as an integrated circuit (semiconductor device) of one chip using a CMOS gate array. The memory access controlling portion 3 may comprise program control using a one-chip microcomputer having a serial communication function built thereinto.

FIG. 7 is a view useful in explaining the names of terminals (signal names) of the integrated circuit for the memory access controlling portion and their functions. Reference RXD denotes an input terminal fora serial data signal supplied by the apparatus main body controlling portion 2. Reference SEL denotes an input terminal for a command mode designating signal (command selecting signal) supplied by the apparatus main body controlling portion 2. Reference TXD denotes an output terminal for a serial data signal supplied to the apparatus main body controlling portion 2. Reference CS1 denotes an output terminal for a selection signal (chip enable signal) for the first non-volatile memory and reference CS2 denotes an output terminal for a selection signal (chip enable signal) for the second non-volatile memory. Reference I01 denotes a data input/output terminal of the first non-volatile memory, and reference I02 denotes a data input/output terminal of the second non-volatile memory.

Reference RW1 denotes an output terminal for a readout/write signal for the first non-volatile memory, and reference RW2 denotes an output terminal for a readout/write signal for the second non-volatile memory. Reference CK1 is an output terminal for a clock signal for the first non-volatile memory, and reference CK2 is an output terminal for a clock signal for the second non-volatile memory. Reference PW1 denotes a power supply terminal for the first non-volatile memory, and reference PW2 denotes a power supply terminal for the second non-volatile memory. References OSC1 and OSC2 denote connection terminals for a ceramic oscillator, a crystal vibrator, and the like. Reference RST denotes an input terminals for an initial reset signal. Reference ES denotes an input terminal for selecting a write time for the non-volatile memory. References M1 to M4 denote input terminals for a testing signal for selecting a monitor output. Reference VCC1 denotes a +5 Voltage power supply terminal, reference VCC2 denotes a +3.3 Voltage power supply terminal, and reference VSS denotes a ground (GND) terminal.

The symbols shown in the input/output column in FIG. 7 have the following meanings: Reference IN denotes an input, reference OUT denotes an output, and reference Tri denotes a tristate-side output. The initial-value column indicates logical levels obtained when this memory access controlling portion integrated circuit is initially reset. Further, the items enclosed by the parentheses in the initial-value column indicate the level of each output terminal obtained immediately after the outputs to the non-volatile memory have been activated following the setting of an access permission in a non-volatile memory access permission setting register, described later. Reference H denotes a high level, reference L denotes a low level, and reference Hi Z denotes a high impedance state.

Three signal lines connect the memory access controlling portion 3 to the apparatus main body controlling portion 2 (see FIG. 1) as shown in FIG. 6. Reference RXD denotes received data (data transmitted from the apparatus main body controlling portion 2), reference TXD denotes transmitted data (data received by the apparatus main body controlling portion 2), and reference SEL denotes a command mode designating signal indicating whether a command transmitted by the apparatus main body controlling portion 2 has a fixed or a variable length. The L level of the command mode designating signal SEL indicates an 8-bit fixed length command, whereas its H level indicates a variable-length command.

A UART (Universal Asynchronous Receiver Transmitter) method is applied to the serial data communicating method. The data length is 8 bits, the start bit length is 1 bit, the stop bit length is 1 bit, and no parity bit is used. Data are transferred from an LSB (Least Significant Bit) to an MSB (Most Significant Bit). The baud rate is 125 kbps.

A reception portion 11 a in the serial-data communicating portion 11 monitors the logical level of the received data RXD with a 0.5-microsecond cycle based on the clock TCLK of 2 MHz frequency supplied by the clock generating portion 22. Thus, one-bit data undergo 16 level detections. Upon recognizing the start bit based on the fact that the logical level of the received data RXD changes from H level to L level, the reception portion 11 a repeats sampling the logical level of the received data RXD with a 16-clock cycle starting from the eighth clock TCLK from the point at which the start bit has been recognized. This allows the logical level of the received data RXD to be sampled substantially at the middle of each bit.

After the start bit has been recognized, if the logical level of the received data RXD returns to H at the next clock, the reception portion 11 a considers the previously detected L level as noise to restart an operation of detecting the start bit. Further, if the logical level of the start bit sampled at the eighth clock TCLK from the point at which the start bit has been recognized is not L, the reception portion 11 a aborts subsequent data sampling and resumes the start bit detecting operation. Furthermore, if the sampling level of the stop bit is not H, the reception portion 11 a invalidates all the sampled data. This prevents reception of abnormal data resulting from different baud rates between the transmitting side and the receiving side or from other factors. Upon normally receiving all of the start bit, 8-bit data, and stop bit, the reception portion 11 a converts the received serial 8-bit data into parallel data and outputs them to the reception controlling portion 12 as parallel received data RD.

A transmission portion 11 b in the serial data communicating portion 11 converts parallel transmitted data TD supplied by the transmission controlling portion 13, into serial data, adds the start bit and the stop bit to the serial data to generate the transmitted data TXD, and transmits the generated transmitted data TXD at a predetermined baud rate.

FIG. 8 is a view useful in explaining various commands supplied by the apparatus main body controlling portion. FIG. 8(A) shows an 8-bit fixed length command supplied by the apparatus main body controlling portion when the command mode designating signal SEL has the L level. There are three types of 8-bit fixed length commands: a power-off process command, an initialization command, and a mode setting command. When the power of the ink jet recording apparatus turns off the power-off process command requests that various data stored in the RAM 17 or 18 are written to the non-volatile memory 4 or 5 and that after the write has been completed, all outputs to the non-volatile memories 4 and 5 are initialized to their reset states established immediately after power-on. The initialization command requests that all the circuits in the memory access controlling portion 3 are initialized to its reset state established immediately after power-on.

The mode setting command sets an operation mode used when the command mode designating signal SEL has become the H level. The mode setting command designates the operation mode with the 4 least significant bits. For example, if the 4 least significant bits are 0010, an operation mode 2 has been set.

The apparatus main body controlling portion 2 is adapted to use 4-bit mode information to manage a plurality of operation modes ranging from modes 0 to 15. For example, the operations of the recording apparatus are commonly controlled in the mode 0, and print data are controlled in the mode 1. In the mode 2, the non-volatile memory can each be accessed via the memory access controlling portion. In the mode 3, a head sensor system is controlled. Even if data transmitted from the apparatus main body controlling portion 2 are supplied to a plurality of control portions (for example, an ink ejection controlling portion, a carriage movement controlling portion, and a sheet feed controlling portion), the designation of an operation mode allows only the control portion compatible with this operation mode to operate based on the data transmitted from the apparatus main body controlling portion 2.

In this embodiment, the memory access controlling portion 3 is adapted to access the two non-volatile memories 4 and 5. Thus, if a plurality of memory access controlling portions 3 are provided and assigned with different operation modes, a large number of non-volatile memories can be accessed. Even if, for example, independent cartridges are provided for inks such as cyan, light cyan, magenta, light magenta, yellow, and black and each comprise a non-volatile memory, then, for example, six non-volatile memories can be accessed by using, for example, three memory access controlling portions 3. In this manner, the operation mode facilitates the extension of the configuration of the recording apparatus.

FIG. 8(B) shows a variable-length command supplied by the apparatus main body controlling portion when the command mode designating signal SEL has the H level. The variable-length command comprises a plurality of bytes. In the first byte, the 4 most significant bits indicate the operation mode and the 4 least significant bits indicate the byte length of this command. The operation mode 2 (0010) is essentially set for commands to the memory access controlling portion 3. The byte length in the 4 least significant bits contains data representative of the byte lengths of the second and subsequent bytes (data representative of the byte lengths of the succeeding bytes exclusive of the first byte).

In the second byte, the 4 most significant bits indicate a command, and the 4 least significant bits indicate a data length. If the 4 most significant bits of the second byte is 0000, this represents a command for a data readout; if it is 1000, this represents a command for a data write. The 4 least significant bits of the second byte contain data indicating the byte length of write data supplied after address data if the command requires a data write, or contain data indicating the byte length of readout data if the command requires a data readout. In this embodiment, up to 4 bytes of data can be supplied with a single write request command.

The third and fourth bytes contain data indicating addresses to or from which data are to be written or read out. The figure shows that the third byte indicates the 8 least significant bits for the addresses, while the fourth byte indicates the 8 most significant bits for the addresses. This makes it possible to designate a wide address range with up to 16 bits. As regards this, in this embodiment, the address range to and from which data are to be written or read out can be designated with 8-bit addresses, so that only the 8 least significant bits of the address data are used. The designated addresses are those in the RAMs and control registers (it is not an address in the non-volatile memories)

The fifth and subsequent bytes contain write data. The data contained in the fifth byte are written to the address indicated by the address data, and the data contained in the sixth and subsequent bytes are written to corresponding incremented addresses starting with the one larger than the address indicated by the address data, by one.

The commands from the memory access controlling portion 3 are roughly divided into two types: level 0 and 1 commands. This command level is selected by means of the command mode designating signal SEL transmitted together with the received data RXD. For example, if the command mode designating signal SEL is low, the command level is 0; if the former is high, the latter is 1. The level 0 command comprises one byte. When this command is received, it is immediately executed. The level 0 command includes an initialization command, a power-off command (NMI), and a mode setting command.

On the other hand, the level 1 command comprises 4 to 8 bytes. When a required number of bytes of this command is received, it is executed only if the state of a mode register set by the level-0 mode setting command is “2”. Otherwise, this command is neglected. The contents of the level 1 command include readouts from or writes to the registers controlling the non-volatile memories 4 and 5 and readouts from or writes to the internal memory.

The command mode designating signal should be kept at a constant level when one command is being transferred.

FIG. 9 is a block diagram of the reception controlling portion. The reception controlling portion 12 comprises eight data latch circuits 12 a to 12 h for latching the parallel 8-bit eight received data RD supplied by the serial data communicating portion 11, and a transfer controlling portion 12 i for controlling the write of the received data RD to the data latch circuit and the transfer thereof to the command executing portion based on the command mode designating signal SEL and the received data RD.

If the command mode designating signal SEL is at the L level (it is for an 8-bit fixed length command), the transfer controlling portion 12 i supplies the received data RD supplied by the serial-data communicating portion 11 to the command executing portion 14.

If the command mode designating signal SEL is at the H level (it is for a variable-length command), the transfer controlling portion 12 i stores the received data RD transferred from the serial-data communicating portion 11, in the first data latch circuit 12 a. The transfer controlling portion 12 i then recognizes the command length of the variable-length command based on the 4 least significant bits of the data stored in the first data latch circuit 12 a. The transfer controlling portion 12 i sequentially stores the received data sequentially supplied by the serial-data communicating portion 11, in the second to eighth data latch circuits 12 a to 12 h. Upon detecting that an amount of received data corresponding to the bytes indicated by the command length have been stored in the data latch circuits, the transfer controlling circuit 12 i transfers the series of data stored in the data latch circuits to the command executing portion 14 and then initializes each of the data latch circuits to allow for the storage of the next variable-length command.

The transfer controlling portion 12 i waits for the next received data to be supplied until a number of data bytes indicated by the command length are received. If the command mode designating signal SEL becomes the L level before a number of data bytes indicated by the command length are received, the transfer controlling portion 12 i initializes all the data stored in the data latch circuits to allow for the reception of the next command. Thus, even while transmitting the variable-length command, the apparatus main body controlling portion 2 can cancel this command by changing the command mode designating signal SEL to the L level.

FIG. 10 is a view useful in explaining timings for switching the command mode designating signal. FIG. 10(A) shows the received data RXD and FIG. 10(B) shows the command mode designating signal SEL. The apparatus main body controlling portion 2 switches the logical level of the command mode designating signal SEL between the stop bit and the next start signal.

The transfer controlling portion 12 i shown in FIG. 9 gives top priority to the designation with the command length if the number of bytes indicated by the command length is unequal to that indicated by the data length. If, for example, the command length indicates a series of 5-byte data, while the data length indicates 4 bytes as the number of data bytes, the transfer controlling portion 12 i determines that all of the series of variable-length commands have been received when 2 bytes of data have been stored in each of the fifth and sixth data latch circuits 12 e and 12 f. The transfer controlling portion 12 i then transfers the data stored in the data latch circuits to the command executing portion 14 to allow for the storage of the next command.

If a mode register, described later, is set to the operation mode 2, the transfer controlling portion 12 i gives top priority to the designation for the operation mode 2 set in a mode register and accepts any command as one for the operation mode 2 (in other words, as a command to the memory access controlling portion) even if the operation mode data (the designation with the 4 most significant bits of the received data stored in the first data latch circuit 12 a) supplied via the serial-data communicating portion 11 indicate an operation mode other than the mode 2.

In this embodiment, three types of data lengths including 1 byte, 2 bytes, and 4 bytes can be set and the data length can be set with 4-bit data. Thus, if data indicating a data length other than these three types are received, the data length is determined to be designated as 4 bytes. Specifically, if data indicating a data length of 3 bytes or 5 to 15 bytes are supplied, the transfer controlling portion 12 i determines that the data length is 4 bytes.

Further, in this embodiment, each address in the RAMs 17 and 18 and the control register 16 can be designated with 8 bits. Thus, the address can be designated only with the lower addresses stored in the third data latch circuit 12 c. Thus, the data on the higher addresses stored in the fourth data latch circuit 12 d are not required to be transferred to the command executing portion 14. Moreover, the fourth data latch circuit 12 d is not required to be provided. In this case, the transfer controlling portion 12 i discards the received data on the higher addresses supplied by the serial-data communicating portion 11 and stores data supplied next to the higher addresses in the fifth data latch circuit 12 e.

When supplied with a command received from the reception controlling portion 12, the command executing portion 14 shown in FIG. 6 interprets and executes that command. When supplied with the mode set command, the command executing portion 14 writes data for the operation mode indicated by the mode set command, to the mode register 15. In this case, the 4-bit data 0010 indicative of a memory access controlling operation mode are written to the mode register 15. The operation mode MD set in the mode register 15 is supplied to the reception controlling portion 12.

When supplied with the initialization command, the command executing portion 14 supplies are set signal generation request to the reset circuit portion 23 to generate a reset signal RS. This initializes (resets) each of the circuit portions of the memory access controlling portion 3.

If the variable-length command is transferred from the reception controlling portion 12, the command executing portion 14 interprets the contents of the variable-length command and executes a process such as a write to or a readout from the group of control registers 16, the first RAM 17, or the second RAM 18.

FIG. 11 is a view useful in explaining specifications on the variable-length command and of a response thereto. This figure shows specifications on the variable-length command (request) in a section (a). The variable-length command includes a readout command (READ) and a write command (WRITE). The mode is set at the 4-bit value (0010), indicating the operation mode 2. The command length indicates the byte length of the command with 4 bits. The 4-bit command value 0000 indicates the readout command, whereas the 4-bit command value 1000 indicates the write command. The data length can be set to 1 byte, 2 bytes, or 4 bytes. Zero byte, 3 bytes, and 5 to 15 bytes are prohibited from being set. The address comprises 16 bits and is designated as 8 least significant bits and 8 most significant bits as shown in FIG. 8. This embodiment uses only the 8 least significant bits. For the write command (WRITE), data to be written are set to comprise sets of 8 bits (bytes).

The portion (b) in FIG. 11 indicates specifications on a response to the read command. The mode is set to the 4-bit value (0010), indicating the operation mode 2. The data length designates the number of bytes of the data responding to the readout command. The data length can be set to 1 byte, 2 bytes, or 4 bytes. Zero byte, 3 bytes, and 5 to 15 bytes are prohibited from being set. Data to be provided as a response are set to comprise sets of 8 bits (bytes).

FIG. 12 is a view useful in explaining the contents of the group of control registers and their functions. The group of control registers 16 comprises a plurality of registers. The group of control registers 16 are assigned with addresses 80 to 92 in the hexadecimal notation.

The address 80 (hexadecimal notation) corresponds to a non-volatile memory access permission setting register in which 2-bit data are set. Each bit is assigned to the corresponding non-volatile memory (each cartridge). The least significant bit is set to indicate whether an access to the first non-volatile memory is permitted, and the most significant bit is set to indicate whether an access to the second non-volatile memory is permitted. The bit value of 0 prohibits the access to the non-volatile memory. In this case, the terminals are set by the output controlling portion 20 as follows: The power supply terminals PW1 and PW2 are in an off state where no power is supplied to the non-volatile memories, and the chip select signal output terminals CS1 and CS2, the clock supply terminals CK1 and CK2, the read/write signal output terminals RWl and RW2, and the data input/output terminals I01 and I02 are all in a high impedance state. The bit value of 1 causes the output controlling portion 20 to set the power supply terminals PW1 and PW2 in an on state where power is supplied to the non-volatile memories. The chip select signal output terminals CS1 and CS2, the clock supply terminals CK1 and CK2, the read/write signal output terminals RW1 and RW2, and the data input/output terminals I01 and I02 are all set in a controllable (active) statebythenon-volatile memory write and read controlling portion 19.

The address 84 (hexadecimal notation) corresponds to a non-volatile memory readout permission setting register in which 2-bit data are set. Each bit is assigned to the corresponding non-volatile memory (each cartridge). The least significant bit is set to indicate whether a readout from the first non-volatile memory is permitted, and the most significant bit is set to indicate whether a readout from the second non-volatile memory is permitted. The bit value of 0 prohibits the readout, whereas the bit value of 1 permits the readout.

The address 85 (hexadecimal notation) corresponds to a non-volatile memory all-area readout setting register. When arbitrary data are written to the non-volatile memory all-area readout setting register (the apparatus main body controlling portion 2 issues a readout command indicating an address in the non-volatile memory all-area readout setting register), all the data stored in the non-volatile memories can be read out via the non-volatile memory write and readout controlling portion 19. However, the access to the non-volatile memories must be permitted before hand and the permission for the readout must be set beforehand.

The address 86 (hexadecimal notation) corresponds to an area storing an all-area readout busy flag indicating that data are being read out from all the areas. The non-volatile memory write and readout controlling portion 19 sets the all-area readout busy flag to one before an all-area readout operation is started, and sets this flag to zero when the all-area readout operation is completed.

The address 88 (hexadecimal notation) corresponds to a non-volatile memory all-area write permission setting register in which 2-bit data are set. Each bit is assigned to the corresponding non-volatile memory (cartridge). The least significant bit is set to indicate whether an all-area write to the first non-volatile memory is permitted, and the most significant bit is set to indicate whether an all-area write to the second non-volatile memory is permitted. The bit value of 0 prohibits the write, whereas the bit value of 1 permits the write.

The address 89 (hexadecimal notation) corresponds to a non-volatile memory all-area write setting register. When arbitrary data are written to the non-volatile memory all-area write setting register (a write operation is performed on the non-volatile memory all-area write setting register), data can be written to all the areas of the non-volatile memories via the non-volatile memory write and readout controlling portion 19. However, the access to the non-volatile memories must be permitted beforehand and the permission for the all-area write must be set beforehand.

The address 8A (hexadecimal notation) corresponds to an area storing an all-area write busy flag indicating that data are being written to all the areas. The non-volatile memory write and readout controlling portion 19 sets the all-area write busy flag to one before an all-area write operation is started, and sets this flag to zero when the all-area write operation is completed.

The address 8C (hexadecimal notation) corresponds to a non-volatile memory limited write permission setting register in which 2-bit data is set. Each 2 bit is assigned to the corresponding non-volatile memory (cartridge). The least significant bit is set to indicate whether a limited write to the first non-volatile memory is permitted, and the most significant bit is set to indicate whether a limited write to the second non-volatile memory is permitted. The bit value of 0 prohibits the limited write, whereas the bit value of 1 permits the limited write.

The address 8D (hexadecimal notation) corresponds to a non-volatile memory limited write setting register. When arbitrary data are written to the non-volatile memory limited write setting register (a write operation is performed on the non-volatile memory limited write setting register), data can be written to limited areas of the non-volatile memories via the non-volatile memory write and readout controlling portion 19. However, the access to the non-volatile memories must be permitted beforehand and the permission for the limited write must be set beforehand.

The address 8E (hexadecimal notation) corresponds to an area storing a limited write busy flag indicating that a limited write is being executed. The non-volatile memory write and readout controlling portion 19 sets the limited write busy flag to one before a limited write operation is started, and sets this flag to zero when the limited write operation is completed.

The address 90 (hexadecimal notation) corresponds to a power-off write permission setting register in which 2-bit data is set. Each bit is assigned to the corresponding non-volatile memory (cartridge). The least significant bit is set to indicate whether a power-off write to the first non-volatile memory is permitted, and the most significant bit is set to indicate whether a power-off write to the second non-volatile memory is permitted. The bit value of 0 prohibits the power-off write, whereas the bit value of 1 permits the power-off write.

The address 92 (hexadecimal notation) corresponds to an area storing a power-off write busy flag indicating that a power-off write is being executed. The non-volatile memory write and readout controlling portion 19 sets the power-off write busy flag to one before a power-off write operation is started, and sets this flag to zero when the power-off write operation is completed. Further, the non-volatile memory write and readout controlling portion 19 sets the contents of the non-volatile memory access permission setting register to initial values (all bits to zero) when the power-off write operation is completed.

The power-off write is executed based on the power-off process command shown in FIG. 8(A). In the power-off write, data are written to over a limited address range from the leading address in the non-volatile memory to a preset predetermined address.

As described previously, data such as the amount of remaining ink, for example, which must be renewed depending on the usage of the recording apparatus are stored within the address range from the leading address in the non-volatile memory to the preset predetermined address. Further, data such as manufacturing conditions for the ink cartridges which are not required to be renewed by the user are stored after the predetermined address. Accordingly, if the recording apparatus is used by the user, data are renewed over the limited address range of the non-volatile memory.

FIG. 13 is a view useful in explaining information stored in the RAM. The RAMs 17 and 18 are configured to contain 8 bits×40 words. In this embodiment, the first RAM 17 is assigned with addresses 00 to 27 in the hexadecimal notation, while the second RAM 18 is assigned with addresses 40 to 67 in the hexadecimal notation.

The first RAM 17 is provided so as to correspond to the first non-volatile memory 4 provided in the black ink cartridge. Various information (information 0 to 34) stored in the first non-volatile memory 4 is read out via the non-volatile memory write and readout controlling portion 19 and stored in the first RAM 17.

The second RAM 18 is provided so as to correspond to the second non-volatile memory 5 provided in the color ink cartridge. Various information (information 35 to 69) stored in the second non-volatile memory 5 is read out via the non-volatile memory write and readout controlling portion 19 and stored in the second RAM 18.

There is registered beforehand in the effective-bit-length data table 21 shown in FIG. 6, the relationship between the information numbers of the information stored in the non-volatile memories and the number of data bits in the information. The effective-bit-length data table 21 also has correlation data between addresses in each of the group of control registers 16 and corresponding effective bit lengths registered therein beforehand. There are also registered beforehand in the effective-bit-length data table 21, correlation data between addresses in the RAMs 17 and 18 and effective bit lengths for data stored at these addresses.

There is registered in the information and address correlating table 26, the correlationship between information numbers and addresses in the RAM where the information is stored.

The non-volatile memory write and readout controlling portion 19 identifies, for each information number, the data of a variable length and in bits which have been read out from the non-volatile memories 4 and 5, by referencing the effective-bit-length data table 21. Then, if the data corresponding to each information number have less than 8 bits, the non-volatile memory write and readout controlling portion 19 adds zeros to the most significant bits to obtain 8-bit data. Further, if the data corresponding to each information number contain 9 bits or more, the non-volatile memory write and readout controlling portion 19 separates the data into the 8 least significant bit positions and the remaining data, and if the remaining data contain less than 8 bits, the non-volatile memory write and readout controlling portion 19 adds zeros to the most significant bit positions to obtain 8-bit data. The non-volatile memory write and readout controlling portion 19 then references the information and address correlating table to write the information each composed of 8 bits to predetermined addresses in the RAMs 17 and 18.

To write the information stored in the RAMs 17 and 18 back to the non-volatile memories 4 and 5, the non-volatile memory write and readout controlling portion 19 performs the readout operation in the reverse order to generate sequential data in bits and of a variable length.

The output controlling portion 20 comprises tristate buffer circuits for driving the output terminals PW, CS, RW, and CK, a bidirectional buffer circuit connected to the IO terminal, circuits for controlling the output state of the tristate buffers, output signal switching circuits for switching an input signal to each buffer circuit between an access state where the non-volatile memories 4 and 5 can be accessed and a test mode, described later, and other circuits.

The tristate buffer circuit for driving the power supply terminals PW1 and PW2 has a high current driving capability. When the access permission setting register of the group of control registers 16 is set to the state where the access to the non-volatile memories is permitted, the tristate buffer circuit with a high current driving capability has its output driven to the H level to cause the power supply terminals PW1 and PW2 to supply power to the non-volatile memories 4 and 5. In this way, according to this embodiment, the power supply controlling means 3 e shown in FIG. 1 is configured through the use of the tristate buffer circuit having high current driving capability provided in the output controlling portion 20.

The non-volatile memory write and readout controlling portion 19 drives the terminals CS, RW, CK, and IO via the output controlling portion 20 to access the non-volatile memories 4 and 5. To read information out from the non-volatile memory 4 or 5, the non-volatile memory write and readout controlling portion 19 changes the chip select terminal CS from L level to H level to make the non-volatile memory 4 or 5 operative, and sets the read-write signal output terminal RW to the L level to set the non-volatile memory 4 or 5 in the readout mode. After the period of time required to establish a data output from the non-volatile memory 4 or 5 has passed, the non-volatile memory write and readout controlling portion 19 reads data out from the leading address the non-volatile memory 4 or 5 by taking in the logical level of the data input/output terminal IO, supplies a clock for incrementing the address in the non-volatile memory, to the clock supply terminal CK to increment the address in the non-volatile memory, and then reads data out from the next address. This operation is repeated until the final address in the non-volatile memory, to read out all the data stored in the non-volatile memory.

To write information to the non-volatile memory, the non-volatile memory write and readout controlling portion 19 changes the chip select terminal CS from L level to H level to make the non-volatile memory 4 or 5 operative, and sets the read-write signal output terminal RW to the H level to set the non-volatile memory 4 or 5 in the write mode. Then, while allowing write data (H or L level) to be output to the data input/output terminal IO, the non-volatile memory write and readout controlling portion 19 changes the clock terminal CK from L level to H level. When the clock signal changes from L level to H level, the non-volatile memory 4 or 5 loads and stores the data at the leading address in a memory cell. Then, the non-volatile memory write and readout controlling portion 19 changes the clock terminal CK from H level to L level to increment the address in the non-volatile memory 4 or 5. The non-volatile memory write and readout controlling portion 19 then allows the outputting of data to be stored at the next address and changes the clock terminal CK from L level to H level to write the data to the next address. This operation is repeated until a predetermined address.

The non-volatile memory write and readout controlling portion 19 comprises a circuit portion for executing writes to and readouts from the first non-volatile memory and a circuit portion for executing writes to and readouts from the second non-volatile memory, in order to simultaneously read out or write back information from or to the two non-volatile memories. Accordingly, readout from and write to the non-volatile memories 4, 5 can be completed in a short time.

When supplied with the variable-length command by the reception controlling portion 12, the command executing portion 14 determines whether the command is for a write or for a readout based on the command (4 most significant bits of the second byte) shown in FIG. 8(B). In this case, if the command composed of 4 bits have the data 0000, it is for a readout; if the command composed of 4 bits have the data 1000, it is for a write. If the command has data other than 0000 or 1000, the command executing portion 14 discards the series of variable-length commands and waits for the next command to be transferred.

When supplied with the write request command, the command executing portion 14 writes the first data (data indicated by the fifth byte of the variable-length command) to the address indicated by the lowest address. When supplied with the second data, the command executing portion write the second data (data indicated by the sixth byte of the variable-length command) to the address larger than the one indicated by the lowest address, by one. When supplied with the third and fourth data, the command executing portion write the third and fourth data (data indicated by the seventh and eighth bytes of the variable-length command) to the addresses larger than the one indicated by the lowest address, by two and three, respectively.

In writing the data to the indicated address, the command executing portion 14 references the effective-bit-length data table 21 to ascertain the effective bit length for the data to be stored at that address. If any bit beyond the effective bit length for the data supplied by the apparatus main body controlling portion 2 has a value of 1, the command executing portion 14 changes the value of this bit to zero before writing the changed data to the corresponding register. When supplied with a command for a write of the 8-bit data 11111111 to the access permission setting register corresponding to the address 80 (hexadecimal notation), the command executing portion 14 ascertains that the effective bit length for the access permission setting register is 2 bits based on the effective-bit-length data table 21, changes the values of bits beyond the effective bit length to zero, and writes the generated data 00000011 to the access permission setting register corresponding to the address 80 (hexadecimal notation).

When supplied with the readout request command, the command executing portion 14 recognizes the number of bytes in the readout request based on the data length (4 least significant bits of the second byte) shown in FIG. 8(B) If the readout request is for one byte, then based on the address indicated by the lowest address, the command executing portion 14 reads out the data stored at this address. If the readout request is for two bytes, then the command executing portion 14 reads data out from the address indicated by the lowest address and from the next address (the indicated address +1). If the readout request is for four bytes, then the command executing portion 14 reads data out from the address indicated by the lowest address and from the addresses equaling the indicated one +1, the indicated one +2, and the indicated one +3.

The command executing portion 14 supplies data on the byte length of the readout data to the transmission controlling portion 13 and then supplies the actually readout data thereto.

FIG. 14 is a block diagram of the transmission controlling portion. The transmission controlling portion 13 comprises five data latch circuits 13 a to 13 e and a transfer controlling portion 13 f. The transfer controlling portion 13 f causes the first data latch circuit 13 a to store the operation mode (0010) in the 4 most significant bits and the data length (the byte length of the readout data) in the 4 least significant bits. The transfer controlling portion 13 f causes the second to fifth data latch circuit 13 a to store the first to fourth readout data supplied by the command executing portion 14. Upon ascertaining, based on the data on the data length, that a predetermined number of data have been obtained, the transfer controlling portion 13 f sequentially transfers the data stored in the data latch circuits 13 a to 13 e to the serial-data communicating portion 11.

The transmission portion 11 b in the serial-data communicating portion 11 shown in FIG. 6 converts the parallel transmitted data sequentially transferred from the transmission controlling portion 13 into serial data and sequentially sends the resulting data to the serial data communicating portion 11, as described previously.

FIG. 15 is a view useful in explaining the format of serial communication data. FIG. 15(A) shows a format used to transmit data less than 8 bits. If 5-bit information is stored in the non-volatile memory as shown in FIG. 15(A){circle around (1)}, the data to be serially transmitted have zeros inserted into the 3 most significant bit positions as shown in FIG. 15(A){circle around (2)} and are transmitted as 1-byte (8-bit) data.

In this manner, the data less than 1 byte are arranged at the least significant bit positions, with zeros placed in the most significant bit positions.

FIG. 15(B) shows a format used to transmits data more than 8 bits. If 10-bit information is stored in the non-volatile memory as shown in FIG. 15(B){circle around (3)}, the 10-bit data are divided into 2-byte data sets for transmission as shown in FIG. 15(B){circle around (4)}. Specifically, the 8 least significant bits of the 10-bit data are first transmitted as the first byte. Then, the 2 most significant bits of the 10-bit data are arranged at the least significant bit positions and zeros are inserted into the most significant bit positions to thereby convert the 10-bit data into 8-bit (1-byte) data, which are then transmitted as the second byte.

The reset circuit portion 24 shown in FIG. 6 generates a reset signal RS, if the logical level of the power-on reset signal RST is L. The circuit portions in the memory access controlling portion 3 are initialized (reset) based on the reset signal RS. Further, when supplied with a reset signal generating signal by the command executing portion 14, the reset circuit portion 24 generates the reset signal RS. Thus, the apparatus main body controlling portion 2 transmits the initialization command shown in FIG. 8(A) to initialize each of the circuit portions in the memory access controlling portion 3.

The oscillating circuit portion 23 comprises a crystal vibrator, a ceramic oscillator X, or the like to generate a raw clock signal of, for example, 16 MHz frequency. The clock generating portion 22 divides the raw clock signal to obtain the clock signal TCLK of, for example, 2-MHz frequency. Further, the clock generating portion 22 generates the clock signals CK1 and CK2 for the non-volatile memories 4 and 5. The clock signals CK1 and CK2 for the non-volatile memories 4 and 5 can have their frequencies switched between two levels depending on the logical level of a clock cycle selecting signal ES. This accommodates non-volatile memories with different write times.

The output controlling portion 20 controls the states of the signal input/output terminals of the non-volatile memories 4 and 5. The testing control portion 25 tests the memory access controlling portion 3 for operation. Normal operational conditions are established when 4-bit testing signals M1 to M4 are set to the L level. If other conditions are set, a test mode is entered, thereby making it possible to output the operational conditions of the internal circuit including the data in the registers and RAMs, to the terminals PW, CS, RW, IO, and CK and other terminals via the output controlling portion 20. This facilitates checking of the operational conditions of the internal circuit.

Next, the operation of the above configuration will be explained. The apparatus main body controlling portion 2 sets the command mode designating signal SEL to the L level and then transmits the initialization command. In receipt of the initialization command, the memory access controlling portion 3 initializes the entire circuit to the same state as that established upon power-on. Then, the apparatus main body controlling portion 2 transmits the mode setting command to cause the mode register 15 in the memory access controlling portion 3 to set the operation mode 2. Thereafter, the apparatus main body controlling portion 2 sets the command mode designating signal SEL to the H level.

After the operation mode 2 is set in the mode register 15 to set the command mode designating signal SEL to the H level, even if the operation mode in a command supplied by the apparatus main body controlling portion 2 is not 2, the memory access controlling portion 3 can accept that command as one for the operation mode 2.

The apparatus main body controlling portion 2 sequentially issues write commands to set a value for each of the group of control registers 16 so that the memory access controlling portion 3 can access the non-volatile memories 4 and 5. Then, the apparatus main body controlling portion 2 issues a write command indicating addresses in the all-area readout controlling register. Thus, the non-volatile memory write and readout controlling portion 19 reads the information stored in the non-volatile memories 4 and 5 and stores the readout information in the RAMs 17 and 18.

The information stored in the non-volatile memories 4 and 5 has different bit lengths for different pieces of information. The non-volatile memory write and readout controlling portion 19 partitions the information by referencing the effective-bit data table 21 in which the contents shown in FIG. 3 are registered.

The non-volatile memory write and readout controlling portion 19 modifies data less than 8 bits to 8-bit data by adding zeros to the missing bit positions, and modifies data more than 8 bits to 2-byte data. The non-volatile memory write and readout controlling portion 19 then stores the data composed of sets of 8 bits, at predetermined addresses in the RAMs 17 and 18 by referencing the information and address correlating table 26 shown in FIG. 13. Thus, all the information stored in the first non-volatile memory 4 is stored in the first RAM 17, while all the information stored in the second non-volatile memory 4 is stored in the second RAM 18.

The apparatus main body controlling portion 2 can obtain various information such as data on the amount of remaining ink, the use start year and month of the cartridges, and ink types, for example, by designating addresses in the RAMs 17 and 18 and issuing a readout request. The apparatus main body controlling portion 2 can also ascertain the current set conditions by reading the contents out from the group of control registers 16.

The apparatus main body controlling portion 2 manages the amount of ink which has been used in connection with the execution of print operations. The apparatus main body controlling portion 2 issues a request for a write of data on the renewed amount of ink to renew the data in the RAMs 17 and 18 relating to the amount of remaining ink.

Before turning off the power supply to the recording apparatus, the apparatus main body controlling portion 2 sets the command mode designating signal SEL to the L level and then transmits the power-off command. When supplied with the power-off command, the memory access controlling portion 3 writes the data stored in the RAMs 17 and 18 back to the non-volatile memories 4 and 5. This causes the renewed data on the amount of remaining ink to be stored in the non-volatile memories 4 and 5. This write back to the non-volatile memories 4 and 5 based on the power-off command is directed only at information (numbers 1 to 9 shown in FIG. 3, specifically, data such as the amount of remaining ink which must be renewed by the user) set at lower addresses in the non-volatile memories 4 and 5. Accordingly, the write back to the non-volatile memories 4 and 5 can be completed in a short time, and no other data are rewritten.

The write back to the non-volatile memories 4 and 5 can also be executed by issuing a command for a write of a command or permitting a limited write to a limited write permitting egister, shown in FIG. 12 from the apparatus main body controlling portion 2.

FIG. 16 is a perspective view showing the structure of a printing mechanism portion of an ink jet printer with a recording apparatus according to the present invention applied thereto. The printing mechanism portion 100 of the ink jet printer apparatus shown in FIG. 16 comprises a carriage 103 connected to a drive motor 102 via a timing belt 101 so as to reciprocate ina sheet width direction of recording paper P. The carriage 103 has a holder 104 formed therein and comprising black ink cartridge storage portion 104 a and a color ink cartridge storage portion 104 b, and has a recording head 105 on the underside of the carriage 103.

FIG. 17 is a perspective view showing that the carriage is disassembled into a holder portion and a header portion. Ink supplying needles 106 and 107 in communication with the recording head 105 is installed on a bottom surface of the carriage 103 so as to lie on a rear side (on the side of a timing belt 101) of the apparatus. Of the walls forming the holder 104, a vertical wall 108, which is close and opposite to the ink supplying needles 106 and 107, has levers 111 and 112 which is attached to an upper end thereof and can be rotationally moved by shafts 109 and 110. A wall 113 located at a free end side of the levers 111 and 112 has a vertical portion 113 a in a bottom side part and an inclined surface portion 113 b in an upper area, the inclined surface portion extending upward in a fashion fanning out.

The levers 111 and 112 have projections 114 and 115 formed to extend from the neighborhoods of the shafts 109 and 110 substantially perpendicularly to the body of the levers 111 and 112, the projections engaging with raised portions 146 and 156 located at upper ends of ink cartridges 140 and 150, respectively. The levers 111 and 112 also have hook portions 118 and 119 that elastically engage with suspension portions 116 and 117, respectively formed on the inclined surface portion 113 b of the holder 104.

The levers 111 and 112 have elastic members 120 and 121, respectively, provided on a rear surface thereof (opposite to a cover 143 of the ink cartridge 140) as shown in FIGS. 20 and 21. The elastic members 120 and 121 elastically press at least areas of the ink cartridges 140 and 150, respectively, which are opposite to ink supply ports 144 and 154 when the ink cartridges 140 and 150 are set in regular positions.

Further, a vertical wall 108 located closer to the ink supply needles 106 and 107 has windows 122 and 123 with an open top portion. Vertical walls 122 a and 123 a and bottom surfaces 122 b and 123 b forming the windows 122 and 123, respectively, have continuous grooves 122 c and 123 c, respectively, formed therein. Contact mechanisms 124 and 125 are inserted and fixed in the grooves 122 c and 123 c, respectively.

The recording head 105 is fixed to the bottom surface of the holder 104 via a horizontal portion 133 of a generally L-shaped base 132. A vertical wall 134 of the base 132 has windows 135 and 136 in areas thereof which are opposite to the contact mechanisms 124 and 125, respectively, with a circuit substrate 130 held in front of the vertical wall 134.

The circuit substrate 130 is connected to the apparatus main body controlling portion 2 via a flexible cable 137 as shown in FIG. 16. The circuit substrate 130 has a gate array IC mounted thereon and constituting the memory access controlling portion 3.

FIG. 18 is a perspective view of the ink cartridge. FIG. 18(A) shows the black ink cartridge 140, and FIG. 18(B) shows the color ink cartridge 150. The ink cartridges 140 and 150 comprise generally rectangular parallelopiped containers 141 and 151 accommodating a porous body (not shown) with ink impregnated therewith, and the covers 143 and 153 sealing top surfaces of the cartridges.

The containers 141 and 151 have the ink supply ports 144 and 145 formed in bottom surfaces thereof and at positions set opposite to the ink supply needles 106 and 107 when the containers are installed in ink cartridge housing portions 140 a and 104 b of the holder 104 shown in FIG. 16. Further, vertical walls 145 and 155 located on the side of the ink supply ports 144 and 145 have the raised portions 146 and 145 integrally formed at upper ends thereof and engaging with the projections 114 and 115 of the levers 111 and 112.

The raised portion 146 of the black ink cartridge 140 is formed to extend continuously from one end to the other end. A triangular rib 147 is formed between a bottom surface of the raised portion 146 and the vertical wall 145. The raised portion of the color ink cartridge 150 is formed individually on opposite sides of the vertical wall. A triangular rib 157 is formed between a bottom surface of the raised portion 156 and the vertical wall 155. Reference numeral 159 denotes a mis-insertion preventing recess portion.

The vertical walls 145 and 155 have recess portions 148 and 158, respectively, located at the center of the ink cartridges 140 and 150 in the width direction, respectively. Non-volatile memory circuit boards 131 and 131 are installed in the recess portions 148 and 158.

FIG. 19 is a view useful in explaining the structure of the non-volatile memory circuit board. FIG. 19(A) is a perspective view showing the front-side structure of the non-volatile memory circuit board 131. FIG. 19(B) is a perspective view showing the rear-side structure of the non-volatile memory circuit board 131. FIG. 19(C) is a view useful in explaining the size of electrodes. FIG. 19(D) is a top view showing how electrodes and contacts contact with one another. FIG. 19(E) is a side view showing how the electrodes and the contacts contact with one another.

As shown in FIG. 19(A), the non-volatile memory circuit board 131 has a plurality of electrodes 160 (160-1 and 160-2) disposed on its surface in two rows in an ink cartridge inserting direction (vertical direction of the figure) and opposite to contact forming members 129 a and 129 b of the contact mechanism 24.

As shown in FIG. 19(B), the non-volatile memory circuit board 131 has an IC chip 161 of the non-volatile memories 4 and 5 mounted on its rear surface. Terminals (not shown) of the IC chip 161 are electrically connected to the contacts 160 via a wiring pattern, through-holes, and the like (not shown). The IC chip 161 of the non-volatile memories 4 and 5 mounted on the non-volatile memory circuit board 131 may be protected by coating it with an ink-resistant material.

As shown in FIG. 19(C), the smaller electrode 160-1 has a height H1 of 1.8 mm and a width W1 of 1 mm. The larger electrode 160-2 has a height H1 of 1.8 mm and a width W1 of 3 mm. The heights of the electrodes 160 a reset so as to reliably 10 contact with the contact forming members 129 a and 129 b even if the ink cartridge 140 or 150 installed in the holder 104 floats.

When the ink cartridges 140 and 150 are installed in the holder 104, the upper contact forming member 129 a of the contact mechanism 24 contacts with the upper electrode 160-1, while the lower contact forming member 129 b of the contact mechanism 24 contacts with the lower electrodes 160-1 and 160-2, as shown in FIGS. 19(D) and 19(E).

As shown in FIG. 19(D), the lower larger electrode 160-2 contacts with the two contact constituting members 129 a and 129 b. Whether or not the ink cartridge is installed is determined by detecting whether or not these two contact constituting members 129 a and 129 b are electrically connected together.

Reference numeral 160T in FIG. 19 denotes an electrode used for checking during a manufacturing process or the like.

The non-volatile memory circuit board 131 has at least one through-hole 131 a or a recess portion (notch) 131 b formed therein.

As shown in FIG. 18, the vertical walls 145 and 155 of the ink cartridges 140 and 150 have projections 145 a, 145 b, 155 a, and 155 b formed thereon and cooperating with the through-hole 131 a or the recess portion (notch) 131 b in the non-volatile memory circuit board 131 for positioning. Furthermore, the vertical walls 145 and 155 have raised portions 145 c, 145 d, 155 c, and 155 d such as ribs or claws which elastically contact with a side surface of the non-volatile memory circuit board 131.

Thus, when the non-volatile memory circuit board 131 is pressed against the vertical walls 145 and 155 of the ink cartridges 140 and 150, the positioning projections 145 a, 145 b, 155 a, and 155 b can position the non-volatile memory circuit 131 and can be engaged with the raised portions 145 c, 145 d, 155 c, and 155 d for installation.

FIGS. 20 and 21 are views useful in explaining how the ink cartridge is installed. FIGS. 20 and 21 show a process of installing the black ink cartridge 140. As shown in FIG. 20, when the ink cartridge 140 is inserted into the holder 104 with the lever 111 opened to a substantially vertical position, the raised portion 146 provided at one end of the ink cartridge 140 is received by the projection 114 of the lever 111, and the other end of the ink cartridge 140 is supported and held by the inclined surface portion 113 b of the holder 104.

In these conditions, when the lever 111 is closed, the projection 114 is rotationally moved downward to cause the ink cartridge 140 to lower while substantially maintaining its position established during an initial period of insertion, so that the ink supplying port 144 comes into contact with a tip of the ink supplying needle 106 as shown in FIG. 21.

When the lever 111 is further rotationally moved, the ink cartridge 140 is pressed via the elastic member 120. The ink supplying port 144 is thereby pushed over the ink supply needle 106. Then, when the lever 111 is fully pushed in, it is fixed to the suspension portion 116 shown in FIG. 17 in such a manner that the ink cartridge 140 is always elastically pressed toward the ink supply needle 106 via the elastic member 120.

The ink cartridge 140 is thereby elastically pressed at a constant pressure with the ink supply port 144 engaged with the ink supply needle 106. Thus, the ink supplying port 144 can remain stably and air-tightly engaged with the ink supplying needle 106 irrespective of impact or vibration associated with vibration during printing or movement of the recording apparatus.

FIG. 22 is a view useful in explaining how the non-volatile memory substrate and the contact mechanism contact with each other. FIG. 22(A) shows a state present before the ink supplying port 144 in the ink cartridge 140 comes into contact with the ink supplying needle 106 of the holder 104. FIG. 22(B) shows that the ink supplying port 144 comes into contact with the ink supplying needle 106. FIG. 22(C) shows that the ink supplying needle 106 is fully inserted into the ink supplying port 144 (the ink cartridge 140 is completely installed).

As shown in FIG. 22(C), when the ink cartridge 140 is completely installed, the terminals (not shown) provided on the non-volatile memory circuit substrate 131 contact with the contact forming members 129 a and 129 b provided in the contact mechanism 124. Contact portions 128 a and 128 b provided at the other end of the contact forming members 129 a and 129 b, respectively, are in contact with the terminals (not shown) provided on the circuit board 130 with the memory access controlling portion 3 mounted thereon. The terminals provided on the non-volatile memory circuit 131 are thereby electrically connected via the contact forming members 129 a and 129 b to the corresponding terminals of the circuit board 130 with the memory access controlling portion 3 (not shown) mounted thereon.

In this embodiment, the ink jet printer apparatus is illustrated as the recording apparatus, but the recording apparatus according to the present invention is applicable to a laser printer apparatus using toner cartridges. Further, the recording apparatus according to the present invention is applicable not only to various printer apparatuses but also to facsimile terminal equipment or various terminal apparatuses comprising a cartridge-replaceable recording mechanism. Furthermore, in this embodiment, the configuration with the two non-volatile memories is shown, but only one non-volatile memory may be used. Moreover, the memory access controlling portion may control writes to and readouts from three or more non-volatile memories.

The above description relates to the particular embodiment of the present invention, and various variations thereof may occur to those skilled in the art and are embraced within the technical scope thereof.

Industrial Applicability

As described above, in the ink jet recording apparatus according to the present invention, the carriage with ink cartridges installed there in has the memory access controlling portion, via which the non-volatile memory is accessed, thereby making it possible to reduce the number of connection lines between the carriage and the control portion of the recording apparatus main body.

The memory access controlling portion and the control portion of the recording apparatus main body transmit and receive various commands and data therebetween by means of serial data communication, there by making it possible to reduce the number of connection lines between the carriage and the control portion of the recording apparatus main body.

The memory access controlling portion has the temporary storage means such as a random access memory in which that data read out from the non-volatile memory are all stored so that the stored data can be read out in response to a data readout request from the apparatus main body controlling portion, thus making it possible to respond to data readout requests at a high speed. Furthermore, after generating a data write request to renew the data in the temporary storage means, the apparatus main body controlling portion can generate a data write request for the non-volatile memory to cause the renewed data to be written to the non-volatile memory. Accordingly, even with a plurality of data items to be renewed, the plurality of data can be written to the non-volatile memory with a single write operation.

Additionally, the memory access controlling portion desirably comprise the power supply controlling means for controlling a power supply to the non-volatile memory; the power supply controlling means enables a power supply to the non-volatile memory only when it is accessed. This makes it possible to reduce unwanted power consumption. Further, the power supply is stopped while the non-volatile memory is not accessed, thereby preventing the data stored in the non-volatile memory from being rewritten due to noise or the like.

The non-volatile memory write and readout controlling means is configured to be able to access a plurality of non-volatile memories, thus preventing the number of connection lines between the carriage and the control portion of the recording apparatus from being increased despite an increase in the number of non-volatile memories.

The use of a semiconductor device (integrated circuit device) for the memory access controlling portion facilitates the provision of the memory access controlling portion in the carriage including the housing portion of the ink carriage and serves to reduce the size of the carriage. 

What is claimed is:
 1. An ink jet recording apparatus comprising: a recording apparatus main body; a carriage moveably mounted to said recording apparatus main body, said carriage including a housing portion; an ink cartridge supported on said housing portion, said ink cartridge including a non-volatile memory; and a memory access controlling portion mounted to said carriage; wherein said memory access controlling portion is adapted to control data transmissions and data receptions between a control portion mounted to said recording apparatus main body and said non-volatile memory.
 2. The ink jet recording apparatus according to claim 1, characterized in that said memory access controlling portion comprises serial data communicating means for executing serial data communication with said control portion of said recording apparatus main body, command executing means for executing a command supplied by said control portion of said recording apparatus main body, and non-volatile memory write and readout controlling means for executing writes to and readouts from said non-volatile memory.
 3. The ink jet recording apparatus according to claim 1, characterized in that said memory access controlling portion comprises serial data communicating means for executing serial data communication with said control portion of said recording apparatus main body, command executing means for executing a command supplied by said control portion of said recording apparatus main body, non-volatile memory write and readout controlling means for executing writes to and readouts from said non-volatile memory, and temporary storage means for temporarily storing data read out from said non-volatile memory.
 4. The ink jet recording apparatus according to claim 1, characterized in that said memory access controlling portion comprises power supply controlling means for controlling a power supply to said non-volatile memory.
 5. The ink jet recording apparatus according to claim 2 or 3, characterized in that said non-volatile memory write and readout controlling means can output plural types of clocks for executing at least either a write to or a readout from said non-volatile memory and select from these clocks depending on electrical characteristics of said non-volatile memory.
 6. The ink jet recording apparatus according to claim 1, characterized in that said memory access controlling portion is configured to access a plurality of non-volatile memories.
 7. A semiconductor device comprising: a semiconductor substrate; a memory access controlling portion formed on said semiconductor substrate; a recording apparatus main body; a control portion on said recording apparatus main body; wherein said memory access controlling portion is adapted to control data transmissions and data receptions between said control portion of said recording apparatus main body and a non-volatile memory; and wherein said control portion of said recording apparatus main body is adapted to supply a command causing execution of said data transmissions and data receptions.
 8. A recording head apparatus comprising: a carriage including a housing portion; an ink cartridge supported on said housing portion, said ink cartridge including a non-volatile memory; and a memory access controlling portion mounted to said carriage; a recording apparatus main body; a control portion on said recording apparatus main body; wherein said memory access controlling portion is adapted to control data transmissions and data receptions between said control portion of said recording apparatus main body and said non-volatile memory; and wherein said control portion of said recording apparatus main body supplies a command causing execution of said data transmissions and said data receptions.
 9. An ink jet recording apparatus comprising: a recording apparatus main body; a carriage including a housing portion supporting an ink cartridge; and a memory access controlling portion including a temporary storage means for temporarily storing data read out from a non-volatile memory in said ink cartridge; wherein said memory access controlling portion is adapted to control data transmissions and data receptions between a control portion mounted to said recording apparatus main body and said non-volatile memory in said ink cartridge.
 10. The ink jet recording apparatus according to claim 9, wherein said memory access controlling portion comprises power supply controlling means for supplying power to said non-volatile memory in said ink cartridge. 